Hydraulic brake mechanism



Aug. 9, 1932.

E. D. JoHNsQN HYDRAULIC BRAKE MECHANISM Filed May 22, 1930 Fig.

Inventor E .1). Johnson BY Ati-Iy,

Patented Aug. 9, 1932 UNITED STATES PATENT OFFICE EDWARD D. JOHNSON, E ST. LOUIS, MISSOURI, ASSIGNOR T0 WAGNER ELECTRIC COB- PORATION, 0F ST. LOUIS, MISSOURI, A CORPORATION 0F DELAWARE HYDRAULIC BRAKE Application led Hay 22,

My invention relates to hydaulic brake -mechanism, one of its objects being to produce a mechanism of this type which will be readily applicable to the landing gear of airplanes.

lA further object of my invention is to provide for ready access to the brake mechanism, permitting adjustment of the working parts, relining the brake shoes, or the like.

In the accompanying drawing, which illustrates one form of brake mechanism made in accordance with my invention, Figure 1 is a vertical cross section through the brake drum; Figure 2 is a section through the wheel and axle, taken in the direction indicated by the line 2 2 of Figure 1; and Figure 3 is a detail view showing the form of the spindle engaging opening in the shield.

Referring irst to Figure 2, 4 indicates an axle of the landing gear of an airplane, which axle is provided on its end with a recessed flange 5. 6 is a spindle provided with a flange 7 secured to the flange 5 by bolts 8 and located concentrically with respect to the axle by means of a centering boss 9 extending into the recess ofthe lange 5. The wheel is formed of a rear disk member 10 and a front disk member 11, shaped as shown and welded or otherwise secured together to provide a wheel disk having an integral hub 12 and rim 13. The tire 14 is detachably secured to the yrim by an annulus 15 attached to I -the disk 10 by screws 16. Interposed be- Uns tween the hub and spindle is an anti-friction bearing 17, preferably of the ball type. Formed in the disk 11 is an integral brake drum 18.

Spindle 6 is provided with a bore 19 to `form the working cylinder of the brake which cylinder contains a piston 2O provided with the usual sealing cup 21 and spring 22. Fluid pressure for operating the piston is supplied through a flexible tube 23 extending through the axle to a suitable source of fluid pressure. In order to allow the escape of air 1930. SeriaI R0. 454,615.

ber, which engage with correspondingslots Y in the end of the spindle, thus elfectively preventing relative rotary movement between the spindle and the shield. Two of these slots are extended backward into the spindle to provide passages 3 for a pair of bell-crank levers 30 pivoted at 31 to brackets carried on the shield. A pair Vof rods 32 connect the levers with toggles 33 for actuating the brake shoes 34.V One end of each Vrod is pivoted at 35 to one of the levers and the other at 36 to the toggle. One end of each toggle turns on a pin 37 carried by the shield and forming the pivot of one of the brake shoes, the other end being pivoted at 38 to the free end of the 'othershoe This construction, securing the maximum braking elect of both shes, is permissible owing to the fact that in airplanes the brakes are only required while the planeto simultaneously apply both brake shoes to' secure maximum braking effect. Upon release of the fluid pressure the springs i retract the shoes.

By utilizing the hollow spindle to contain the working cylinder and `a portion of the wheel disk to form the brake drum, a construction is Secured having at the same time light weight and great strength and rigidity. Furthermore, removal of thel shield, carrying the brake shoes and their operating connections, gives ready access to both the brake and working cylinder for repairs or adjustment. Another advantage -of my construction is that it may be applied to any type of landing gear by providing the ends of the axle with recessed flanges of the vproper dimensions. Y

Having fully described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. In a device of the class described, the

combination with a hollow wheel spindle, of,

a piston within and movable longitudinally of said-spindle, a wheel mounted on said spindle and provided with a brake drum, a

brake shoe for said drum movable in a plane transverse to the spindle, and operating con- V'nections between said piston and brake shoe.

2. In a device of the class described, the

, combination with a hollow spindle, of a piston in said spindle, a wheel mounted rotatively on said spindle and provided with a brake drum, a. brake "shoe forO said drum, and operating connections including a bell-crank lever between said piston and brake shoe.

3. In a device of the class described, the combination with a hollow wheel spindle, of a piston in said spindle, a wheel having a hub embracing said spindle, said wheel also comprising a disk member shaped to form a brake drum, a brake shoe for said drum, and operatlng connections between said piston Y andbrake shoe.

4. In a device of the class described, the combination with a hollow wheel spindle, of

a piston in said spindle, a wheel having a hub embracing said spindle and provided wlth a brake drum, a shield for said drum mounted on the outer end of said spindle, and

a brake shoe and operating connections therefor mounted on said shield, said connections being actuated by said piston.

5. In a device of the class combination with a hollow spindle, of a piston 1n said spindle, a wheel mounted on said described, the

spindle and having a disk member shaped to form a brake drum, a shield for said drum, a brake "shoe mounted on said shield, a bellcrank lever also mounted on said shield and bearing on said piston, and connections 'between said bell-crank lever and brake shoe.

6. In a device of the Yclass described,vthe combination with a hollow spindle, of a piston in said spindle, a wheel mounted on said splndle, said wheel comprising front and rear disk members forming a hub and tire tread, 

